使用注解做添加删除修改
注解类：package com.sql.annotation;import java.lang.annotation.ElementType;import java.lang.annotation.Retention;import java.lang.annotation.RetentionPolicy;import java.lang.annotation.Target;@Retention(RetentionPolicy.RUNTIME)@Target(ElementType.TYPE)public @interface TableNameAnnotation {public String table();}package com.sql.annotation;import java.lang.annotation.ElementType;import java.lang.annotation.Retention;import java.lang.annotation.RetentionPolicy;import java.lang.annotation.Target;@Retention(RetentionPolicy.RUNTIME)@Target(ElementType.FIELD)public @interface ColumnNameAnnotation {public String column();}注解处理器：public class SQLProcessor {private static Map methodMap = new HashMap();public static String getAnnotationName(Object obj,Class annotationClazz, String name) throws Exception {String value = null;Annotation annotation = null;Class clazz = obj.getClass();if(clazz.isAnnotationPresent(annotationClazz)) {annotation = clazz.getAnnotation(annotationClazz);} else {throw new Exception("没有需要处理的注解");}Method method = annotation.getClass().getMethod(name, null);value = (String) method.invoke(annotation, null);return value;}public static int createInsertSQL(Connection conn, Object obj) throws Exception {String str1 = "insert into ";String tableName = "";String str2 = "(";StringBuffer columnNmaes = new StringBuffer();String str3 = ") values (";StringBuffer params = new StringBuffer();String str5 = ")";Map map = new HashMap();tableName = getAnnotationName(obj, TableNameAnnotation.class, "table");Field[] fields = obj.getClass().getDeclaredFields();int index = 1;for (Field field : fields) {ColumnNameAnnotation annotation = field.getAnnotation(ColumnNameAnnotation.class);if(annotation == null) {continue;} else {columnNmaes.append(annotation.column()).append(",");params.append("?").append(",");String typeName = field.getType().toString();int tempIndex = typeName.lastIndexOf(".");String type = null;if(tempIndex > 0) {type = typeName.substring(tempIndex+1);} else {type = typeName;}field.setAccessible(true);map.put(type.toLowerCase()+"," + index, field.get(obj));index++;}}int deleteIndex = columnNmaes.lastIndexOf(",");int deleteIndex2 = params.lastIndexOf(",");String columnName = columnNmaes.toString().substring(0, deleteIndex);String param = params.toString().substring(0, deleteIndex2);StringBuffer sql = new StringBuffer();sql.append(str1).append(tableName).append(str2).append(columnName).append(str3).append(param).append(str5);PreparedStatement pstat = conn.prepareStatement(sql.toString());setSqlParameter(pstat, map);return pstat.executeUpdate();}public static void setSqlParameter(PreparedStatement pstat, Map map) throws SQLException {Set keySet = map.keySet();Iterator<String> iterater = keySet.iterator();for(;iterater.hasNext();) {String key = iterater.next();String[] keyAndIndex = key.split(",");int type = (Integer) methodMap.get(keyAndIndex[0]);int parameterIndex = Integer.valueOf(keyAndIndex[1]);switch (type) {case 1:pstat.setInt(parameterIndex, ((Integer)map.get(key)));break;case 2:pstat.setFloat(parameterIndex, Float.valueOf((String)map.get(key)));break;case 3:pstat.setDouble(parameterIndex, (Float)map.get(key));break;case 4:pstat.setByte(parameterIndex, (Byte)map.get(key));break;case 5:pstat.setLong(parameterIndex, (Long)map.get(key));break;case 6:pstat.setShort(parameterIndex, (Short)map.get(key));break;case 7:pstat.setTime(parameterIndex, (Time)map.get(key));break;case 8:pstat.setTimestamp(parameterIndex, (Timestamp)map.get(key));break;case 9:pstat.setString(parameterIndex, (String)map.get(key));break;case 10:pstat.setDate(parameterIndex, (Date)map.get(key));break;case 11:pstat.setBoolean(parameterIndex, (Boolean)map.get(key));break;default:break;}}}static {methodMap.put("int", 1);methodMap.put("float", 2);methodMap.put("double", 3);methodMap.put("byte", 4);methodMap.put("long", 5);methodMap.put("short", 6);methodMap.put("time", 7);methodMap.put("timestamp", 8);methodMap.put("string", 9);methodMap.put("date", 10);methodMap.put("boolean", 11);}}测试实体类：@TableNameAnnotation(table="departments")public class Department {private int did;@ColumnNameAnnotation(column="department_name")private String departmentName;public int getDid() {return did;}public void setDid(int did) {this.did = did;}public String getDepartmentName() {return departmentName;}public void setDepartmentName(String departmentName) {this.departmentName = departmentName;}}测试类：public static void main(String[] args) throws SQLException, SecurityException, NoSuchFieldException {Department depart = new Department();depart.setDepartmentName("gggg");//从ibatis获得ConnectionSqlMapClient client = SQLMapClient.getSqlMaper();Connection conn = client.getDataSource().getConnection();SQLProcessor processor = new SQLProcessor();try {int b = processor.createInsertSQL(conn, depart);System.out.println(b);System.out.println("-------------------------------------");conn.commit();conn.close();} catch (Exception e) {e.printStackTrace();}}